DSA legal basis validations

[bretg]

Pulling the legal basis validation check out of https://github.com/prebid/prebid-server/issues/3438 for further discussion:

if dsaparams in the response contains nonconsented reasons for selecting the ad, toss the response, using this table to map params to tcf2 consent strings (via an activity layer) https://github.com/prebid/Prebid.js/pull/10982#issuecomment-1919709446

Basically, we need to discuss how to position these checks relative to the Activity Controls